Metal deactivators



United States Patent 3,190,835 METAL DEACTIVATORS Wilhelm C. BrezesinskaSmithuysen, Daniel van Velzen, Jacob C. Caron, and Wim de Bruine, all ofAmsterdam, Netherlands, assignors to Shell Oil Company, New York, N.Y.,a corporation of Delaware N0 Drawing. Filed June 28, 1961, Ser. No.120,178 Claims priority, application Netherlands, July 29, 1960, 254,3617 Claims. (Cl. 252-47) This invention relates to improved hydrocarbonoils and particularly to gasoline, kerosene and transformer oilcompositions having improved oxidation stability.

It is known that certain hydrocarbon oils such as motor fuels boilingwithin the gasoline boiling range, i.e., gasoline produced from thecracking of petroleum, have an undesirable tendency to undergodeterioration on storage, with loss in such valuable properties as lightcolor, low gum content and antiknock values. Moreover, blends of theseunstable gasoline compositions with more stable gasolines, such asstraight run gasoline, frequently also show a tendency to deteriorateupon storage. This oxidative deterioration of hydrocarbon oils isconsiderably ac celerated by traces of polyvalent metals nearly alwayspresent in these materials. Copper in particular has a greataccelerating effect on oxidative deterioration of most hydrocarbon oilsduring storage. As a result, the acid number and sludge content oftransformer oil, for example, may increase to such an extent that theoil has to be renewed, whereas in gasoline the gummy products formed bythis catalyzed deterioration often later cause fouling of enginecarburetor and fuel lines.

It is known that the catalytic oxidative effect of certain polyvalentmetals in hydrocarbon oils can be neutralized by the addition of certaincomplexing compounds to these materials. Most of the complexingcompounds used today are derivatives of salicyclaldimine, i.e., havingthe general structural formula:

In addition, compounds in which two of these groupings are bound by, anethylene bridge are often used. The corresponding ketimine derivativesas well as derivatives from amino-phenol and from anthranilic acid arealso employed.

The above types of complexing compounds, however, all have thedisadvantage in that they contain a functional group capable of reactingwith alkali also present in the hydrocarbon oil. The resultantalkali-metal deactivator salts, will not form complexes with thecatalytically active polyvalent metals. In addition the alkalimetalsalts formed are water-soluble, therefore during storage, theyaccumulate in the separating aqueous phase and are ultimately lost.

It is an object of this invention to provide hydrocarbon oilcompositions with improved stability. It is a further object of theinvention to increase the oxidative stability of certain gasolinecompositions without affecting the detonation resistance of the gasolineand without increasing either the toxicity of the fuel composition orits tendency to lay down combustion chamber deposits. A still furtherobject of the invention is to provide improved hydrocarbon oilcompositions containing metal deactivator compounds which are effectivein the presence of alkali. The attainment of these and other objectswill be apparent from the detailed description of the invention which isa hydrocarbon oil composition containing small but critical amounts ofcertain complexing agents, capable of forming complexes with polyvalentmetals in the presence 31,190,835 Patented June 22, 1965 ice of alkali,and which, in the presence of an alkaline or non-alkaline aqueous phasewill not pass into that phase.

X Bil Wherein each R can be a hydrogen atom, an alkyl radical, an arylradical, an aralkyl radical or an alkaryl radical or the two Rs togetherwith the wherein each R can be an imino radical or an alkylene radicalcontaining from 1 to 3 carbon atoms and each X is a nitrogen-containingheterocyclic radical containing from 3 to 9 carbon atoms bonded to R inthe 2-position such as Z-thiazolyl, 2-pyridyl, 2-quinolyl and2-isopyrrolyl radicals.

In an also preferred embodiment of the invention, disubstituted diphenylpyrroline compounds are used as the complexing agent. These materialshave the structural formula:

R-X Cairo-i;

\NH 0,13 -o ,ii-X

Wherein each R can be an amino radical or an alkylene radical containingfrom 1 to 3 carbon atoms and each X is a nitrogen-containi-ngheterocyclic radical containing from 3 to 9 carbon atoms bonded to R inthe 2-position such as Z-thiazoly-l, 2-pyridyl, 2-quinolyl, and2-isopyrrolyl radicals.

It has now been discovered that the addition of the class of compoundsof Formula I to hydrocarbon oils such as gasoline, kerosene, gas :oiland transformer oil, unexpectedly improves the stability of thesehydrocarbon oils even in the presence of alkali. For example,diasubstituted isoindol-ine compounds are capable of complexing variouspolyvalent metals which act as oxidative catalysts even when thesemetals are in hydrocarbon oils containing 1-(2'-quino1y1imin0)3-(2'-isopyrr0lylimin0) isoindoline, l.e.,

and 2,5-di(2 pyridy1imin0)3,4-diphenyl-pyrroline, i.e.,

and the certain materials which can be more readily de- 39 fined bysetting forth their structural formula, i.e.

CHaCHg alkali. This result is particularly significant sinceconventional metal deactivators added to hydrocarbon oils in thepresence of alkali fail to exhibit these complexing properties and thusfail to impart improved oxidative stability to the hydrocarbon oilcompositions.

Specific examples of the complexing compounds of the invention are:

1,3-di(2-pyridylimino)-isoindoline, i.e.;

1,3-di(2-thiazolyli1nino)-isoindo1ine, i.e.,

l. 063 orn The various 1,3 substituents of the isoindoline compounds and2,5 substituents of the pyrroline compounds above are preferably limitedto nitrogen containing heterocyclic radicals which are bound to theisoindoline or pyrroline compound in the 2-position. 7

It was discovered that the complexing agents of the invention such asthe di-substituted isoindoline compounds of the invention improve theoxidative stability of hydrocarbon compositions containing alkali andcertain polyvalent metal, that is when the materials of Formula I areadded to gasoline compositions in concentrations sufficient todeactivate the oxidation catalyzing metals contained therein, thesemetal deactivating compounds did not become water soluble uponextraction of the gasoline with alkali, whereas, conventionaldeactivators became water soluble and were readily extracted fromgasoline with water and/or aqueous sodium hydroxide, when similarlytreated.

For example 1,3-di(2'-pyridylimino)-isoindoline, 2,5-di-(2-pyridylimino)3,4-diphenylpyrroline and 1,3-di(2'-thiazolylimino)-isoindoline were dissolved in a gasoline.1,3-di(2-pyridylimino)-isoindoline was prepared by the method desired byI. A. Elvidge and R. P. Linstead, I.

\ Chem. Soc., 1952, p. 5000 et seq., whereas the two other examples,2,-B-di(2'-pyridylimino)3,4-diphenyl-pyrroline and1,3-di(2-thiazolylimino)-isoindoline, were prepared as follows:

2,5-di(2'-pyridylimin0)3,4-diphenylpyrr0line.-A Il'liX- ture of 100parts by weight of 1,2-diphenyl-1,2-dicyanoethene and 90 parts by weightof 2-aminopyridine were heated for 3 hours at 220 C. Evolution ofammonia occurred. The melted mass was dissolved in 4000 parts by weightof boiling n-butanol. The solution was cooled down to 12 C. and thecrystallized product filtered and washed with pentane. The yieldamounted to 90 parts by Weight of2,5-di(2-pyridylirnino)3,4-diphenyl-pyrroline in the form of black-greencrystals.

Analysis.-Carbon 77.7% w., hydrogen 5.1% w., nitrogen 17.0% w.Calculated for C H N carbon 77.8% w., hydrogen 4.7% W., nitrogen 17.4%w.

1,3 di(2' thiazolylimino) isind0line.20 parts by weight ofZ-amino-thiazole and 14.5 parts by weight of 1,3-di-imino-isoindolinewere dissolved in 400 parts by weight of isobutanol. The solution wasboiled under reflux for 8 hours. Evolution of ammonia took place. Aftercooling 20 parts by weight of green-colored crystals was obtained. Aftercrystallizing in 6400 parts by weight of isobutanol the yield was 18parts by weight of 1,3-di(2- thiazolylimino)-isoindoline in the form ofgreen-yellow needles. The melting point was 277 C.

Analysis.Nitrogen content 22.6% w. Calculated for C H N S nitrogencontent 22.5% W.

In the following l,3-di(2'-pyridylimino)-isoindoline is indicated asCompound A, 2,5-di(2'-pyridylimino)3,4-diphesnyl-pyrroline as Compound Band l,3-di(2-thiazolylimino) isoindoline as Compound C. Compound A,Compound B and Compound C each were dissolved in a catalytically crackedgasoline having a boiling range of from about 40 to 200 C., in aconcentration of 2.5 p.p.m., 5 p.p.rn. and 6.7 p.p.m., respectively. Theresultant gasoline compositions were extracted with water and an aqueoussolution of sodium hydroxide. A similar exraction was also carriedoutwith a catalytically cracked gasoline containing 2.5 p.p.m. ofdisalicylal-ethylene diamine, a conventional metal deactivator. Theresult of these extractions are set forth below in Table I.

TABLE I Percent of Percent compound of di- Extracting agent extractedsalicylalethylene diamine. A B O extracted 10 by vol. of water having apH of 6.0. 0 10% by vol. of a 0.1 by wt. caustic soda solution 0 10 byvol. of a 1.0 wt. caustic soda solu on 0 0 0 100 2 by vol. of a 5 wt.caustic soda solution 0 100 1 by vol. of a 10 by wt. caustic sodanlntinn 0 100 1 by vol. of a 30 by wt. caustic soda solution 0 0 Theoxidative stability of a catalytically cracked gaso line having aboiling range of from about 40 C. to about 200 C. and containing copperin catalytic concentrations, i.e., containing a copper coil strip equalto about 1 sq. cm. of copper per 20 ml. of gasoline, was tested with andwithout the addition of 10 ppm. of 1,3-di(2- pyridylimino)-isoindoline,by storing the gasoline composition, in the atmosphere in an open glassvessel.

The induction period of the gasoline in fresh conditions and after ithad been stored for one week was determined by ASTM Method D525. Thecopper content of It is evident from the data set forth above that thecopper chelate formed by the 1,3-di(2-pyridylimino)- isoindoline is notcatalytically active, so that there is no catalyzed oxidativedeterioration of the gasoline.

The induction period of a catalytically cracked gasoline having aboiling range of from about 40 to about C. was determined by ASTM MethodD525. Copper napththenate was then dissolved in the gasoline and theinduction period determined. The induction period of similar gasolinescontaining Compounds A, B and C and copper naphthenate were alsodetermined. The results are set forth in Table III below.

A catalytically cracked gasoline having a boiling range of from about 40to about 190 C. was treated with 10% by volume of a 1% by weight causticsoda solution. Cop per naphthenate was then dissolved in the treatedgasoline. A similar gasoline was treated with caustic soda in the sameway and copper napthenate and Compound A were then dissolved in thetreated gasoline. 'Similar gasolines containing the Compounds A, Band Cwere treated with caustic soda as'described above and copper naphthenatewas then dissolved in the treated gasoline. The induction periods of thegasolines were determined by ASTM Method D525. The results are set forthin Table IV.

The oxidative stability of caustic-treated similar gasolines containingdisalicylal-ethylene diamine was also de- 5" termined using ASTM MethodD525. These results are set forth in Table V.

TABLE III Concentration, Concentrap.p.m. of tion of copper Inductioncompound naphthenate period,

expressed as minutes p.p.m. copper A B O Catalytically cracked TABLE IVInduction period in minutes Gasoline treated with caustic soda solution300 Gasoline treated with caustic soda solution and then 0.5 p.p.m. ofcopper as copper naphthenate added Gasoline treated with caustic sodasolution and then 0.5 p.p.m. of copper as copper naphthenate and 6p.p.m. of Compound A added Gasoline containing 6 p.p.m. of Compound Atreated caustic soda and then 0.5 p.p.m. of copper as copper naphthenateadded Gasoline containing 5 p.p.m. of Compound B treated with causticsoda and then'0.5 p.p.m. of copper as copper naphthenate added Gasolinecontaining 6.7 p.p.m. of Compound C treated with caustic soda and then0.5 p.p.m. of copper as copper naphthenate added 195 TABLE V Inductionperiod in minutes Gasoline containing 0.5 p.p.m. copper as coppernaphthenate and 3 p.p.m. of disalicylal-ethylene diamine 280 Gasolinecontaining 3 p.p.m. of disalicylal-ethylene diamine 320 Gasolinecontaining 3 p.p.m. of disalicylal-ethylene diamine treated with causticsoda and then 0.5 p.p.m. of copper naphthenate added 120 It is readilyapparent from the results set forth in Table III that the addition ofcopper naphthenate has an adverse effect on the oxidative stability ofthe gasoline tested and that metal deactivators of Formula I, i.e., 1,3-di(2'-pyridylimino)-isoindoline, 2,5-di(2 pyridylimino)3,4-diphenyl-pyrroline and 1,3-di(2-thiazoly1in1ino)-isoindoline arecapable of counteracting this adverse effect. It can also be seen fromTable III as well as from Table II, that even in the absence of coppernaphthenate or copper, the stability of gasoline is further improved bythe addition of Formula I type compounds. The data set forth in Table IVand in Table V show that the Formula I type compounds are resistant totreatment with a caustic soda solution, whereas conventional metaldeactivators, such as disalicylal ethylenediamine, are not.

The stability of a mineral oil fraction containing 1,3- di(2'pyridylimino) isoindoline was examined in the S.E.V. test (PublicationNo. 124, Regeln fiir Isolieriil, by the SchweizeriseherElektrotechnischer Verein, January 1, 1936). The mineral oil fractionwas a naphthenic spindle oil extracted with sulphur dioxide and having aviscosity of approximately 80 SUS at 100 F. This oil was tested as suchand after the addition of 0.01% and 0.02% by weight respectively of1,3-di(2'-pyridylimino)- isoindoline and disalicylal ethylenediamine.The oil was heated to 110 C. in a copper beaker for seven days, a

copper bar provided with a cotton thread winding being present in theoil. The results of these tests are set forth in Table VI below.

In addition to being effective in improving the oxidative stability ofhydrocarbon oils such as gasoline, kerosene, gas oil, transformer oiland crankcase lubricating oils, the metal deaetivators of Formula I canalso be used .in specialty products such as mineral spirits, paintsolvents and the like. Particularly beneficial results are generallyachieved in the case of liquid hydrocarbon products and especiallyhydrocarbon distillates.

The improvement in the oxidative stability of various hydrocarbons bythe use of the compounds of Formula I may be obtained over a wide rangeof concentrations, that is, the concentration of these materials may beas low as 0.1 p.p.m. and as high as 150 p.p.m. depending upon theparticular material in which it is incorporated, the severity of theconditions to which the hydrocarbon is to be subjected and the length oftime the hydrocarbon base must be protected against deterioration. Forexample, in most gasolines, jet fuels and other hydrocarbon distillates,the lower concentrations are ordinarily sufficient, that is, up to about15 p.p.m. and particularly about 1 to about 10 p.p.m. are preferred.

In a preferred embodiment of the invention the metal deactivator ofFormula I is'used in gasoline fuels. The stabilized gasoline fuelcompositions of this invention include thermally or catalyticallycracked, thermally or catalytically reformed gasolines or products ofsulphuric acid or hydrochloric acid alkylation of lower molecular weightolefins and isoparaffins, e.g., of butylene and isobutane and mixturesthereof. Automotive gasoline fuel compositions having a boiling rangefrom about the boiling points of C to C hydrocarbons to about 450 F.,are suitable as the hydrocarbon base of the invention. These fuels willpreferably have an ASTM Method D-86 distillation range of from about toF. to about 357 to 425 F.

In addition to the metal deactivator, the stabilized gasoline fuelcompositions of the invention will preferably contain anoctane-improving amount of an organo-lead antiknock agent, i.e., a leadantidetonant, such as tetralower-alkyl lead compound, for exampletetraethyllead, tetramethyllead, diethyl .dimethyl .lead, ethyltrimethyl lead, methyl triethyl lead and mixtures thereof. Theconcentration of the lead antiknock agent is generally at least 0.5 cc.per gallon and up to 6 cc. per gallon, more especially at least 1 cc.per gallon and no more than 4 cc. per gallon. When a lead antiknockagent is used a halohydrocarbon scavenger such as ethylene dibromide ora mixture of ethylene dibromide and ethylene dichloride will usually beaddedin conjunction therewith, especially in an amount-of from about 1.0to about 1.5 or 1.6 theories, 1.0 theory being the amount necessary toprovide two atoms of halogen per atom of lead in the lead antiknockagent present. The gasoline compositions of the invention can alsocontain other antiknock agents such as iron-pentacarbonyl,dieyclopentadienyl iron, xylindene, N-methylaniline, and theorgano-manganese compounds such as described in Brown et al., US.2,818,417, December 31, 1957, especially methylcyclopentadienylmanganese tricarbonyl, or bis(cyclopentadienyl) manganese.

Other additives which may be added to the gasoline compositions of theinvention include the various antiicing agents such as the mono-N-alkylsubstituted propylenediamines; combustion chamber deposit modifiers suchas esters of boric acid, for example, isopropyl 2-methyl-2,4-pentanediol borate, 2-methyl-2,4-pentanediol monoacid borate,bis(1,1,3-trimethyl trimethyleneoxy) boric acid, and the like; corrosioninhibitors such as polymerized linoleic acids and N,C-disubstitutedimidazolines; metal deactivators such as N,N-disalicylal-1,2-propanediamine; and dyes, silicone oils, and the like.

In addition to the compositions described above, a suitable example of agasoline composition for use of the invention is set forth below:

Catalytic reformate percent v 70 Straight run gasoline percent v 301,3-di(2-isopyrrolylimino)-isoindoline p.p.m Tetraethyllead cc./ gal-2.8 Ethylene dibromide theory 0.5 Ethylene dichloride do 1.0 Tricresylphosphate do 0.3

The lubricating oils to which the compounds of Formula I are added arepreferably mineral oils. They can be parafiin base, naphthene base ormixed paratfin-naphthene base distillate or residual oils. Lubricatingoils having an SUS viscosity of 100 F. between about 50 and 1,000 may beused. These lubricating oils will usually contain other additives suchas detergents and dispersants. A preferred lubricating oil for use inthe invention is a non-ash forming mineral oil within the SAE -30Wrange.

The following are illustrative examples of compositions suitable for useaccording to the invention.

Example I Transformer oil containing p.p.m. of 1,3-di(2'-pyridylethylene) -isoind oline.

Example ll Kerosene containing p.p.m. of 1,3-di(2'-quinolyln-propylene-isoindoline.

Example III Gasoline containing 5 p.p.m. of 1-(2'-thiazolylimino)- 3-(2-pyridy1imino -iso-indoline.

Example IV Gasoline containing 1 p.p.m. of 1,3-di(2'-pyridylimino)-isoindoline.

Example V Gas oil containing 50 p.p.m. of 1,3-di(2-isopyrrolylimino)-isoindoline.

Example VI Mineral lube oil having a viscosity of 320 SUS at 100 F.containing 5 ppm. of 1-(2'-isopyrrolylimino)-3-(2- quinolyl-methylene)-isoindoline.

Example VII Kerosene containing 20 p.p.m. of a complexing agent havingthe structural formula:

Inc-ii mo U 10 Example VIII A gasoline composition contain 10 p.p.m. ofa complexing agent having the structural formula:

Example IX A lubricating oil containing 5 p.p.m. of a complexing agenthaving the structural formula:

l: l l 1 l l A 0g OH OH Example X A gasoline composition containing 10p;p.m. of a complexing agent of the formula:

wherein R is selected from the group consisting of hydrogen, alkyl,aryl, aralkyl and alkaryl, with the proviso that the carbon atoms withinthe R groups which are in the beta position relative to N can be membersof a nonacetylenically-unsaturated S-membered hetenocyclic ring in whichN is the hetero atom, R is selected from the '1 1 group consisting ofimino and alkylene having from 1 to 3 carbon atoms, and X is aheterocyclic nitrogencontaining radical, bonded to R in the 2-position,selected from! the group consisting of Z-thiazolyl, 2-pyridyl, 2-quinolyl, and 2-isopyrroly1.

2. A composition according to claim 1 wherein the hydrocarbon i1 is agasoline fuel.

3. A composition according to claim 1 wherein the hydrocarbon oil iskerosene.

4. A composition according to claim 1 wherein the hy- 10 drocarbon oilis a crankcase lubricating oil having an SUS viscosity at 100 F. ofbetween 50 and 1000.

5. A liquid hydrocarbon oil containing 0.1-150 p.p.m. by weight of1,3-di(2-thiazolylimino)-isoindolinc.

6. A liquid hydrocarbon oil containing 0.1150 p.p.m. 15 by weight of1,3-di(2'-pyridylimino)-isoindo1ine.

312 v '7. A liquid hydrocarbon oil containing 0.15O p.p.m. by weight of2,5-di(2-pyridylimino) 3,4-diphenyl-pyrroline.

References Cited by the Examiner UNITED STATES PATENTS 2,492,048 12/49Klabunde 252 401XR 2,595,140 4/52 Heinrich 252-50 2,787,551 4/57 Bell eta1. 44-63 XR 2,864,676 12/58 Thompson 4463 DANIEL E. WYMAN, PrimaryExaminer.

JULIUS GREENWALD, Examiner.

1. A LIQUID HYDROCARBON OIL, NORMALLY CONTAINING TRACE AMOUNTS OF ALKALIAND POLYVALENT OXIDATIVE CATALYZING METALS, HAVING IMPROVED OXIDATIVESTABILITY CONTAINING 0-1-150 P.P.M. BY WEIGHT OF A COMPLEXING AGENTCAPABLE OF FORMING COMPLEXES WITH POLYVALENT METALS IN THE PRESENCE OFALKALI HAVING THE STRUCTURAL FORMULA